The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Some embodiments relate to methods applied to a well bore penetrating a subterranean formation.
Hydrocarbons (oil, condensate, and gas) are typically produced from wells that are drilled into the formations containing them. For a variety of reasons, such as inherently low permeability of the reservoirs or damage to the formation caused by drilling and completion of the well, the flow of hydrocarbons into the well is undesirably low. In this case, the well is “stimulated” for example using hydraulic fracturing, chemical (usually acid) stimulation, or a combination of the two (called acid fracturing or fracture acidizing).
Hydraulic and acid fracturing of horizontal wells as well as multi-layered formations frequently requires using diverting techniques in order to enable fracturing redirection between different zones. The list of these diverting methods includes, but not limited to, using mechanical isolation devises such as packers and well bore plugs, setting bridge plugs, pumping ball sealers, pumping slurred benzoic acid flakes and removable/degradable particulates. As well, other treatment may require use of diverting techniques.
Treatment diversion with particulates is typically based on bridging of particles of the diverting material behind casing and forming a plug by accumulating the rest of the particles at the formed bridge. Several typical problems related to treatment diversion with particulate materials are: reducing bridging ability of diverting slurry during pumping because of dilution with well bore fluid (interface mixing), necessity of using relatively large amount of diverting materials, and poor stability of some diverting agents during pumping and during subsequent treatment stage.
Diversion involving degradable particles has become popular in the industry since it enables better control of the producing fractures and thus improved hydrocarbon recovery. Different materials have been used with different degree of success; however, some challenges remain particularly at high temperature since the kinetics of degradation are still difficult to control. Methods disclosed herewith offer innovative way to create diverting techniques, zonal isolation or techniques thereof.